docs: def pprint(self, imports=None, prefix="\n    ",unknown_value='<?>',
                 qualify=False, separator=""):
          """
          Same as Parameterized.pprint, except that X.classname(Y
          is replaced with X.classname.instance(Y
          """
          r = Parameterized.pprint(self,imports,prefix,
                                   unknown_value=unknown_value,
                                   qualify=qualify,separator=separator)
          classname=self.__class__.__name__
          return r.replace(".%s("%classname,".%s.instance("%classname)